Sureace marking device



p 1 1945. R. B. MEN'II'ZER 2,385,014

SURFACE MARKING DEVICE Filed June 13, 1941 3 Sheets-Sheet 1 41 PH 5. mavrzz-z v A TTORNEYS.

fl INVENTOR.

Sept. 18, 1945. R. B. MENT ZER 2,335,014

' SURFACE MARKING DEVICE Filed June 13. 1941 3 Sheets-Sheet 2 v BY map/ a ja /5 7??? E I ATTQRNEYS.

Sept. 18 1945. R MENTZER 2,385,014

SURFACE MARKING DEVICE Filed June 13, 1941 3 Sheets-Sheet 3 IN V EN TOR. RAMP/9 8. Nf/W'Zff Z? ATTORNEYS.

operator. Also, it has been found impractical from a cost and quality standpoint to produce such designs on the parts of small watches by the usual method of lapping. Since many small watche are ladies watches which need the utmost in beauty, decorative designs are important in the sale of such watches.

The present invention obviates the above difficulties and disadvantages by providing an automatic milling device and method which produces decorations of the damascene typ and of a quality favorably comparable therewith. This device and method substantially reduces the cost the tool spindle and with the spindle tilted with respect to the surface of the workpiece so that upon rotation of the spindle, the cutting edge of the tool travels in a circle and comes in contact with the workpiece during a portion only of the circumference of the circle. The workpiece is progressively moved past the rotating tool so that the decorative mark formed on the workpiece takes the form of a series of separate lines,

aligned with each other in the form of a path or flute and extending transversely thereof, with the cut in the workpiece formed by the tool not only curved in the depth of the workpiece, that is with the out having shallow end portions and "aielatively deep central portion, but also curved in the plane of the surface of the workpiece.

The path'or flute extends in the direction of 'movement of the workpiece past the tool during the forming of the path.

The tool is so formed and positioned as to produce cuts of good reflective ability throughout so that when finished no undesirable shadows appear. As is shown in Fig.-XI, which illustrates the type of'cut formed, the cross section is such that reflected light rays from any part of the out are readily directed upwards out of the cut'and are not trapped by any overhang of the cut in such amanner as to produce undesirable shadow efiect. Instead, the entire surface of th cut is bright, and light reflections are such as to pro- -'vide the desired daniascene-like effect of moving highlights upon relative movement between the decorated surface and the eye.

The formation of the designs of applicants invention may be entirely carried out through the use of one tool and associated unit as illustrated in Fig. 2511 or through the use of a plurality'of'tools and units as illustrated in Fig. I.

Automatic operation of the single unit of Fig. XlII may be accomplished by moving the work table I, past the tool holder 2 a plurality of times in the same direction, while indexing a step in a transverse direction for each movement since ordinarily it isdesirable to have the flute'or path of cuts of less width than the width-of the workpiece so that several flutes will appear on a single piece as is illustrated in Fig. X[. By careful control of the speed of rotation of the tool, the speed of movement of the work table past the tool, the

-tool before the indexing cam is brought into tilting of the tool with respect to the surface of the work, the shaping of the cutting edge or edges of the tool, the depth to which the tool is allowed to cut, the radius of the-circle through which the cutting portion of the tool swings, and such factors as keeping the work table quite level, the unit as illustrated in Fig. XIII is made automatic.

Automatic operation of the device of this in vention using a single spindle is illustrated in Figs. XEII-XV and differs from the operation of the multiple unit of Fig. I only in that the single spindle forms all of the flutes on a single workpiece by forming one flute andthen indexing sideways to the next flute position.

Provision for the indexing is made in that the angle piece is is slidable in a dovetail slide l5 of the upport M. The angle piece l3and, accordingly, the tool is normally urged along the slide l5 in a direction away from the work table I by weight member 45 acting through a flexible connecting member 46 over a pulley 41. This movement is resisted during the forming of a single path or flute by means of a lever 48 pivoted to the angle piece l3 at 49 and having a tooth 5!] engaging with a tooth of a rack 5| mounted on the base M. The tooth 50 is normally held engaged with the rack 5| through the action of the spring 52 on the lever 48. The spring 52 has one end connected to the lever 48 and the other end to the base [4 so as to constantly pull the lever 48 downward about its pivot 49.

As the work table 1 moves past the tool in a direction effectively normal to the illustration a single path or flute is formed on the workpiece. The table I is provided with a cam member 53 which is so mounted and formed as to intercept the lever 48 as the table is moved past the tool, and raise it about its pivot 4.9 so as to momentarily disengage the tooth 50 from the rack 5|. This disengagement permits the weight 45 to move the angle piece IS a step away from the work table I and since the angle piece supports the tool holder 2 and the motor 53 the en tire unit is moved and the'tool is in position for the next path or flute'to be formed on the workpiece 5 beside the first path.

If desired more than one work chuck may be positioned on the work table I when only one tool is used,'and.all of the chucks passed beneath the action, that is; a first flute is formed on each of the workpieces and then the tool is indexed to position the tool for the second flute all around. Fig. XV illustrates such an arrangement in which the table lis traveling in the direction of the arrow 54, the work 5 on the chuck 55 has just had a flute formed therein and the work on the chuck 56 has previously in the same single cycle of the table I had'a similarly positioned flute formed thereon and the lever 48 is about to engage the cam 53 so as to index the angle piece l3 and accordingly the tool in the tool holder 2 away from the table I so as to start the second cycle and form a second flute on the workpieces 5.

When-the unit of Figs. I and II is utilized it is not necessary to move the same work piece repeatedlypast the same spindle in order to comwork piece.

plete the work but instead each spindle is so adjusted as to form a separate flute on the same The work table I has a series of work chucks 3 thereon and the chuck 3 supports a cam 4, Fig. V, which is adapted to move the tool holder 2 away irom the work piece 5 whenitis desired .to pre- The earn 4 may be used on as many of the chucks 3 as desired since adjustment oi cam screw 4:2 may be made to keep the cam dent-of operation when (desired. If several-oi the chucks haveoams on them and it is desiredto 115156 \only someloi the :CamS :at one time and all at another, some of the teams may he made higher than the others so that at one adjustment of com screw 4 the higher cams only would operate and eat a lower ndiustmentof :the :cam :screw... all of the cams would operate.

Ilhe toolspimlle 6 iszmount-ed for rotation in a hracket 1 land is driven from a z-belt 6 throughn pulley i. The tool 5.9 is mounted in the tool holder :2 withrits cutting edge in :oficenter relation to the spindle 6.. The shaft 6 :has :a sleeve .l'll fixed thereon and 'a spring M acting against sleeve in in :oneldirection and against thebracket .1 in the other so as to constantly urge theshatt 6 downwardly in the direction of the wonkand to take iupwertical end thrust on the spindle without damage to the tool, without the necessity of moving the whole spindle unit upward against the action .N the relatively strong spring to take care :of possible stool vibrations or chatter operation. v

*bracket F! supports the cam screw I12 the head of which extends downwardly and is adapted to contact the cam 4 of the work chuck 3. The cam screw I2 is adjustably mounted in the flower pontion of the thracket I so that it may be: caused to contact difiereot :camsof :diii'erent heights or it may be so adjusted .as to be kept .out of operation entirely instances Wheniit is desired to cover the entire .surfiace of the work piece with the .decoratice design. The action of moving the tool away-from the work upon the contact of the mm :screw 12 with the cam 4 is made possible through the mounting of the bracket 1 for'vertical movement with respect to plate l6 which is pivotally mounted .at l?! on the angle piece l-l. Plate 116 and :bracket 1 and, accordingly the tool holder :2, are pivoted as a unit about the hor-i- "zontalpiyot H on the angle-piece 13 to permit the tool shaft :5 to be angled with respect to the vertical so that with the tool 58 properly adj-us'ted through screw 18 for vertical position itwi-l-l contact the work piece 5 only during a "portion of each of its rotations in accordance with its offcenter relation wit'h' thetool spindle 5.

The angle piece l3 supports the plate 16 and unit is used, that is, one tool, this adjustment is automatically made after each time the work is moved past the tool so as to present a new and fresh surface to the tool through the automatic indexing action of cam 53, Fig. XV.

When the tool units are used in groups as illustrated in I the angle pieces 13 are adjusted on the bases I' l along their grooves 1 5 to different positions so that one tool will form 'the first flute and the next tool will form the *fiute beside V it and so on" until the entire surface of the 'workpiece hasbeendecorated and without the workpi hav gwpassed any one of the. tools more than once, 1

The unit comprising-the bracket 1 and plate .ti is in adjusted position about the pivot 4 1 in the (angle piece J3 by a screw J8 which is threaded into the :plate 4-6 and which lies in the slot I29 in the angle piece I3". The slot 19 permits {at least sufiicient lateralmovement of the screw 4.8 when the bracket .1 is moved about the pivot I! to permit tool spindle *6 to be angled sufliciently with respect no the workpiece 5 to cause-the tool to out the work during a portion only of 7680b revolution of. the tool.

The bracket 1 is mounted-on the plate Hi by means: of the dovetail slide 18a. The plate t6 supports :a top piece 29 in which an adjustment stop pin 1:8 :is mounted. The pin. 18 has is. head member 2-1 which-acts :as :a stop when moved against {the top piece 28 and limits the downward movement of the rtool :so as to :accurately and rigidly iix zthe anaximmn downward extent of the cutting action :ofthe-tool; The lower end :of the pin H is threaded into (the bracket .1 to permit vertical adjustment of. the tool. The pin I 8 also has a stop member 22' below the top plate 2:0 to prevent excessive upward. movement of the bracket], and is so positioned on the pin 18 as to provide: suflEicien-t space below the. plate 20 to permit the operation :of any ofthe oams 4. The bracket. 1' is urged downwardly by a spring 23 which hastone end fixed oothe plate 16 and the other on the bracket 1. The bearing of the member 21 against the top plate 2 U limits the down-ward movement of the bracket f under the action :of the spring 2 3.

When the cam screw l2 contacted by the cam 1 the bracket 1 is lifteuilum'd moved along the dovetail slide [9a within the limits provided bet-ween the stop 22 and the "topplate '20. The vertical position offthe cutting edge of the tool '2 with respect to workpiece may be varied by adl us'tment of the screw 48 which moves the bracket 1 vertically-relative to 'theywork table I.

The work ch-uck *3 comprises a fixed holding plate 2-4 and a holding plate 25 movable along a spring pressed shaft 26 and a cam lever '21 adapted to hold the jaws of the chuck open or closed depending upon the position of the cam fever 2?. The chuck is opened or shut by the rno-vezinent of the plate 15 along the shaft 26, away from, or toward the fixed plate 24. The shaft 56 has two coil springs mounted thereon, see Fig. "X, one of which, at 60, ismounted between the head 61 of the shaft 245 and "the plate 2 5. When the chuck is closed, as in Fig. VII, spring 611 is compressed through the tightening action of com 62 of the lever 21, and the plate 25 is held against the-workpiece 5.

When the lever 11 is moved about its pivot 63 tothe low point of cam 62, spring is released to "a 'pointwhere it has relatively no action in either direction. When thecompression of spring Ed is thus released, the second spring, at 6'4,

' which bears on plate 25*and the body of the chuck 3, mov es the plate 25 along the shaft 26 toward the head 61 thus opening the chuck and relieving the holding pressure on the workpiece 5.

The holding pressure of the plate 2 5 having been removed, the workpiece is moved upward an amount siifiEwierit to perm-it it to be readily picked up. under the actior-i of a pin 65 and spring 66. The spring 66 backed up by a holding screw "61'.

""As shown in Fig. X the workpiece 5 has a plurality of locating pins 31" and the chuck member 3 has depressions therein suitably placed to receive these pins so as to bring about a'desired initial position of the workpiece. The clamping action of the plate'25, pushing the workpiece against the fix'edplate 24, accurately locates the workpiece, since theplates 24 and '25 have workpiece engaging edges formed to complimentary contours of the edges of the workpiece to be held therebetween.

In many cases, particularly-watches, it is desirable to have decorative designs of the type described on a plurality of separate and/or interchangeable pieces which are placed adjacent each other in their proper assembled positions, for instance, the various bridges and plates of a watch, and to have the flutes orlines of the design follow along in uniform and aligned relation from one piece to the'other. For this reason the preliminary locating recesses and the workpiece contours are formed in the chucks 3 and each workpiece is positioned and held on the chuck in such a manner as,to give its decorations the desired positional relation with the other-decorations on the other pieces when the various pieces are assembled-in theirynormal relation with each other.

Gr'oupsof the unitsxsuch as illustrated in Fig. XML-maybe utilized as shown in Fig. I withoutwthe automatic indexing arrangement of cam 53 and lever 48, to provide a continuously operating, automatic machine with each unit performing a different operation on the workpiece, that .is, each;unit is so-positioned as to form one of the several flutes on the workpiece so that when the workpiece has once moved'past all of the tols;its entire surface as far as is desired has been covered.

This automatic unit comprises a work support in the; form ofa rotatable annular plate I mounted on a table 29 which is in turn supported by a baseor pedestal 30. The annular plate l is adapted to rotate on the table 29 about the arbor 3| of the table 29 and on a film of oil which: is. supplied from an oil reservoir 32 in the plate 29 and drawn between the lower surface ofthe plate I and the surface of the table 29 which the plate overlies.

.The annular plate I has gear teeth on its peripheral edge and is rotated through a worm gear in connection with the teeth of the plate periphery and a reduction gearing 3-3 and a pulley and. has agroup of work holder chuck mem- ,bers 3 spaced about its periphery.

The-table 29 has an outer shoulder 35 on is fixedly mounted a group of tool units such as that illustrated in-Fig. v, with the bases l4 mounted ontheshoulder 35 so that the angle gpiece l3 and accordingly the tool member may be moved along thedovetailslides l5 to move the I-,carriesthe chucks around beneath the Various -tool units so that each tool forms one flute on each workpiece. The tools are so adjusted as to completely cover the workpiece, insofar as is de- -sired, with the recora'tive design, by forming one flute persp'mdie" with the flutes side'by side.

One rotation of the annular plate I, or at least sufficient rotation of that plate to move the workpiece past all of the operating spindles, is sufficient to complete the desired design on the workpiece. The spindles 6 are driven by individual motors 36 which are mounted on the bases [4 of the tool holding units and one motor is made'to drive two of the tool units, although one motor could be made to drive one or more than two of the units if desired.

The path or flute formed on a workpiece by one of the tools or by the tools of this invention may be made to whatever contour is desired. In the arrangement shown in Fig. I the path will be slightly curved in accordance with the radius of the work support I. The radius may be made greater or-less as desired by forming the work support I to greater or less diameter, or the workpieces may be made to pass beneath the tools in a straight line or any desired curve by otherwise varying the nature and motion of the work supporting plate. 3

The angling of the tool shaft 6 with respect to the workpiece 5 and chuck 3 is illustrated in Fig. IV. The shaft is at an angle with the workpiece 5 and the tool holder 2, see Fig. VIII, has the tool member 59 mounted thereon with its cutting edge in off center relation with the shaft 6; This illustrates the movement of the tool, that is, during a portion only of eachof its revolutions it cuts into the workpiece and during the remainder of the revolution it swings in the air and has no cutting action on the workpiece so that as it is moved past the workpiece it forms a series of separate curved lines thereon. A plan view of a typical workpiece which is a part of a watch and which has a finished design thereon is shown in Fig. XI illustrating the curved separate lines which are incomplete portions of circles and the paths or flutes formed thereby.

A very important featureof this-invention is the provision of reflecting surfaces throughout the cuts formed by the tool. It is essential to have the proper reflection since it is this reflection' which gives the beauty to the design. A cross section of the cut enlarged andpartially taken along the line of XIIX]1 in Fig. XI is shown in Fig. XII, and illustrates the cross section of the cuts at their deepest points. The tool is so formed and sharpened that the cut surface in both of the portions indicated at 40 and 4| are given a brightness so that a proper reflection is 'produced throughout the out.

What I claim is: 1. In a device'of the character described, a supporting member, asubstantially circular plate member mounted on said support for rotation about a vertical pivot'and on a film of lubricant, a plurality of workholders mounted onsaid plate in spaced arrangement about the-periphery adjustable with respect thereto about a horizontal pivot, a tool spindle bracket mounted on said intermediate member for straight line adjustment normally substantially vertically with respect thereto, a relatively strong spring so mounted as to tend to move said tool bracket with respect to said intermediate member, a tool spindle mounted for rotation and for longitudinal sliding movement in said tool bracket and a relatively weak spring so mounted as to tend to move said spindle longitudinally of itself in said tool bracket.

2. An apparatus for surface decoration comprising a support, a circular plate member mounted for rotation about a vertical axis carried by said support, workholders affixed to said support at spaced intervals and equidistant from the center, said workholders each supporting a single workpiece, means for scoring a plurality of series of arcs on each workpiece, each series being progressively farther from the center of said plate member by less than the extent of the arc and means associated with said workholders and said scoring means governing the cutting action of said scoring means on said workpieces.

v3. An apparatus for surface decoration comprising a support, a circular plate member rotating in a horizontal plane and carried by said support, a series of chucks each supporting a workpiece carried. by said member, and means for cutting an are at progressive instants, both in time, and distance from the center of said member, said arcs forming a plurality of series of semi-circular lines and means associated with said chucks and said cutting means governing the cutting action of said cutters on said workpieces.

4. An apparatus for surface decoration comprising a support, means for moving a plurality of workpieces about a common center, a series of rotating cutters arranged at progressively increasing radial distances from said center and in the path of said workpieces, and means for rotating said cutters at a speed proportional to the speed of the moving workpieces that a plurality of series of arcs are formed on the surface of the workpiece, the overlapping of the adjacent series forming lines concentric with the path of travel of the workpieces and a cam engaging a supporting frame for said rotating cutters to control the extent of said cutting operation.

RALPH BENDER MENTZER. 

